# Nereididae > Mediated Wiki article. Canonical URL: https://mediated.wiki/source/Nereididae > Markdown URL: https://mediated.wiki/source/Nereididae.md > Source: https://en.wikipedia.org/wiki/Nereididae > Source revision: 1350632737 > License: Creative Commons Attribution-ShareAlike 4.0 International (https://creativecommons.org/licenses/by-sa/4.0/) Family of annelid worms Not to be confused with [Neriidae](/source/Neriidae) or [Nerillidae](/source/Nerillidae). Nereididae Alitta succinea Scientific classification Kingdom: Animalia Phylum: Annelida Clade: Pleistoannelida Subclass: Errantia Order: Phyllodocida Suborder: Nereidiformia Family: Nereididae Blainville, 1818 **Nereididae** (formerly spelled **Nereidae**) are a family of [polychaete](/source/Polychaeta) worms. It contains about 500 - mostly-marine - species grouped into 42 genera. They may be [commonly](/source/Common_name) called **ragworms** or **clamworms**. ## Characteristics The [prostomium](/source/Prostomium) of Nereididae bears a pair of [palps](/source/Palp) that are differentiated into two units. The proximal unit is much larger than the distal unit. [Parapodia](/source/Parapodia) are mostly-[biramous](/source/Biramous) (only the first two pairs are uniramous). [Peristomium](/source/Peristomium) fused with the first body-segment, with usually two pairs of tentacular [cirri](/source/Cirrus_(biology)). The first body-segment with 1-2 pairs tentacular cirri without [aciculae](/source/Acicula). Compound [setae](/source/Seta) are present. [Notopodia](/source/Notopodium) are distinct (rarely reduced), usually with more flattened lobes, [notosetae](/source/Notoseta) compound [falcigers](/source/Falciger) and/or [spinigers](/source/Spiniger) (rarely notosetae absent). They have two prostomial [antennae](/source/Antenna_(biology)) (absent in *Micronereis*). Their [pharynx](/source/Pharynx), when everted, clearly consists of two portions, with a pair of strong jaws on the distal portion and usually with conical teeth on one or more areas of both portions. Most genera have no [gills](/source/Gills) (if present, they are usually branched and arise on mid-anterior segments of body). The [larval](/source/Larva) body consists of four segments. ### Jaw-material Ragworms' teeth are made of a very tough, yet lightweight material. Unlike [bone](/source/Bone) and [tooth enamel](/source/Tooth_enamel), this is not mineralized with [calcium](/source/Calcium), but is formed by a [histidine](/source/Histidine)-rich protein, with bound [zinc](/source/Zinc) ions.[1] Research on this material could lead to applications in engineering.[2] ## Systematics Nereididae are currently considered a [monophyletic](/source/Monophyletic) taxon. Their closest neighbours in polychaete [phylogenetic tree](/source/Phylogenetic_tree) are Chrysopetalidae and [Hesionidae](/source/Hesionidae) (the superfamily Nereidoidea). Nereididae are divided into 42 genera, but the relationships between them are as yet unclear. The family contains traditionally three subfamilies - Namanereidinae, Gymnonereinae and Nereidinae. ### Genera Subfamily [Gymnonereidinae](https://en.wikipedia.org/w/index.php?title=Gymnonereidinae&action=edit&redlink=1) Banse, 1977[3] - *[Australonereis](https://en.wikipedia.org/w/index.php?title=Australonereis&action=edit&redlink=1)* Hartman, 1954 - *[Ceratocephale](/source/Ceratocephale)* Malmgren, 1867 - *[Dendronereides](https://en.wikipedia.org/w/index.php?title=Dendronereides&action=edit&redlink=1)* Southern, 1921 - *[Gymnonereis](https://en.wikipedia.org/w/index.php?title=Gymnonereis&action=edit&redlink=1)* Horst, 1919 - *[Kinberginereis](https://en.wikipedia.org/w/index.php?title=Kinberginereis&action=edit&redlink=1)* Pettibone, 1971 - *[Leptonereis](https://en.wikipedia.org/w/index.php?title=Leptonereis&action=edit&redlink=1)* Kinberg, 1865 - *[Micronereides](https://en.wikipedia.org/w/index.php?title=Micronereides&action=edit&redlink=1)* Day, 1963 - *[Olganereis](https://en.wikipedia.org/w/index.php?title=Olganereis&action=edit&redlink=1)* Hartmann-Schröder, 1977 - *[Rullierinereis](https://en.wikipedia.org/w/index.php?title=Rullierinereis&action=edit&redlink=1)* Pettibone, 1971 - *[Sinonereis](https://en.wikipedia.org/w/index.php?title=Sinonereis&action=edit&redlink=1)* Wu & Sun, 1979 - *[Stenoninereis](https://en.wikipedia.org/w/index.php?title=Stenoninereis&action=edit&redlink=1)* Wesenberg-Lund, 1958 - *[Tambalagamia](https://en.wikipedia.org/w/index.php?title=Tambalagamia&action=edit&redlink=1)* Pillai, 1961 - *[Tylonereis](https://en.wikipedia.org/w/index.php?title=Tylonereis&action=edit&redlink=1)* Fauvel, 1911 - *[Tylorrhynchus](/source/Tylorrhynchus)* Grube, 1866 - *[Typhlonereis](https://en.wikipedia.org/w/index.php?title=Typhlonereis&action=edit&redlink=1)* Hansen, 1879 - *[Websterinereis](https://en.wikipedia.org/w/index.php?title=Websterinereis&action=edit&redlink=1)* Pettibone, 1971 Subfamily [Namanereidinae](/source/Namanereidinae) Hartman, 1959[3] - *[Namalycastis](/source/Namalycastis)* Hartman, 1959 - *[Namanereis](https://en.wikipedia.org/w/index.php?title=Namanereis&action=edit&redlink=1)* Chamberlin, 1919 Subfamily [Nereidinae](https://en.wikipedia.org/w/index.php?title=Nereidinae&action=edit&redlink=1) Blainville, 1818[3] - *[Alitta](/source/Alitta)* Kinberg, 1865 - *[Ceratonereis](/source/Ceratonereis)* Kinberg, 1865 - *[Cheilonereis](https://en.wikipedia.org/w/index.php?title=Cheilonereis&action=edit&redlink=1)* Benham, 1916 - *[Composetia](https://en.wikipedia.org/w/index.php?title=Composetia&action=edit&redlink=1)* Hartmann-Schröder, 1985 - *[Eunereis](https://en.wikipedia.org/w/index.php?title=Eunereis&action=edit&redlink=1)* Malmgren, 1865 - *[Hediste](/source/Hediste)* Malmgren, 1867 - *[Imajimainereis](https://en.wikipedia.org/w/index.php?title=Imajimainereis&action=edit&redlink=1)* de León-González & Solís-Weiss, 2000 - *[Laeonereis](https://en.wikipedia.org/w/index.php?title=Laeonereis&action=edit&redlink=1)* Hartman, 1945 - *[Leonnates](https://en.wikipedia.org/w/index.php?title=Leonnates&action=edit&redlink=1)* Kinberg, 1865 - *[Micronereis](https://en.wikipedia.org/w/index.php?title=Micronereis&action=edit&redlink=1)* Claparède, 1863 - *[Neanthes](/source/Neanthes_(annelid))* Kinberg, 1865 - *[Nectoneanthes](https://en.wikipedia.org/w/index.php?title=Nectoneanthes&action=edit&redlink=1)* Imajima, 1972 - *[Nereis](/source/Nereis)* Linnaeus, 1758 - *[Nicon](/source/Nicon_(annelid))* Kinberg, 1865 - *[Paraleonnates](https://en.wikipedia.org/w/index.php?title=Paraleonnates&action=edit&redlink=1)* Chlebovitsch & Wu, 1962 - *[Parasetia](https://en.wikipedia.org/w/index.php?title=Parasetia&action=edit&redlink=1)* Villalobos-Guerrero, Conde-Vela & Sato, 2022 - *[Perinereis](https://en.wikipedia.org/w/index.php?title=Perinereis&action=edit&redlink=1)* Kinberg, 1865 - *[Platynereis](/source/Platynereis)* Kinberg, 1865 - *[Potamonereis](https://en.wikipedia.org/w/index.php?title=Potamonereis&action=edit&redlink=1)* Villalobos-Guerrero, Conde-Vela & Sato, 2022 - *[Pseudonereis](https://en.wikipedia.org/w/index.php?title=Pseudonereis&action=edit&redlink=1)* Kinberg, 1865 - *[Simplisetia](https://en.wikipedia.org/w/index.php?title=Simplisetia&action=edit&redlink=1)* Hartmann-Schröder, 1985 - *[Solomononereis](https://en.wikipedia.org/w/index.php?title=Solomononereis&action=edit&redlink=1)* Gibbs, 1971 - *[Unanereis](https://en.wikipedia.org/w/index.php?title=Unanereis&action=edit&redlink=1)* Day, 1962 - *[Wuinereis](https://en.wikipedia.org/w/index.php?title=Wuinereis&action=edit&redlink=1)* Khlebovich, 1996 Subfamily Nereididae *incertae sedis*:[3] - *[Kainonereis](https://en.wikipedia.org/w/index.php?title=Kainonereis&action=edit&redlink=1)* Chamberlin, 1919 - *[Lycastonereis](https://en.wikipedia.org/w/index.php?title=Lycastonereis&action=edit&redlink=1)* Nageswara Rao, 1981 ## Ecology Ragworms are predominantly marine organisms that may occasionally swim upstream to rivers and even climb to land (for example *[Lycastopsis catarractarum](https://en.wikipedia.org/w/index.php?title=Lycastopsis_catarractarum&action=edit&redlink=1)*). They are commonly found in all water depths, foraging in seaweeds, hiding under rocks, or burrowing in sand or mud. Ragworms are mainly [omnivorous](/source/Omnivorous) but many are active [carnivores](/source/Carnivore). Nereids breed only once before dying ([semelparity](/source/Semelparity_and_iteroparity)), and most of them morph into a distinct form to breed ([epitoky](/source/Epitoky)). Ragworms are important food sources for a number of shore-birds.[4] ## Human use *[Chả rươi](/source/Ch%E1%BA%A3_r%C6%B0%C6%A1i)* (an omelete made of *Tylorrhynchus heterochetus*) is considered a delicacy in [Vietnam](/source/Vietnam). Ragworms such as *[Hediste diversicolor](/source/Hediste_diversicolor)* are commonly used as [bait](/source/Fishing_bait) in sea-[angling](/source/Recreational_boat_fishing).[5] They are a popular bait for all types of [wrasse](/source/Wrasse) and [pollock](/source/Pollock). They are also used as fish-feed in [aquaculture](/source/Aquaculture).[6] Ragworms, such as *[Tylorrhynchus heterochetus](/source/Tylorrhynchus_heterochetus)*, are considered a delicacy in [Vietnam](/source/Vietnam) where they are used in the dish [chả rươi](/source/Ch%E1%BA%A3_r%C6%B0%C6%A1i).[7] In rice-growing areas of China, these worms are harvested from the rice-fields and are often cooked with eggs. In [Thailand](/source/Thailand), ragworms have occasionally been reported in tap water supply systems in [Chachoengsao Province](/source/Chachoengsao_Province). They are often broadly grouped with other marine polychaetes, and are commonly associated with members of the family [Syllidae](/source/Syllidae) found in [Bangkok](/source/Bangkok) water systems, which are locally referred to as *tua roi khā* ([Thai](/source/Thai_language): ตัวร้อยขา,lit. 'hundred-legged creatuares') or *tua Songkran* (ตัวสงกรานต์, Songkran creatuares). They are frequently reported in tap water systems during the summer season, particularly around the [Songkran](/source/Songkran) festival period (13–15 April), which coincides with Thailand's hottest months.[8] ## References Wikimedia Commons has media related to [Nereididae](https://commons.wikimedia.org/wiki/Category:Nereididae). 1. **[^](#cite_ref-1)** Broomell et al. (2008) [Cutting Edge Structural Protein from the Jaws of Nereis virens](http://pubs.acs.org/doi/abs/10.1021/bm800200a) Biomacromolecules, 9 (6), pp 1669–1677. 1. **[^](#cite_ref-2)** [Marine Worm's Jaws Say 'Cutting-Edge New Aerospace Materials'](https://www.sciencedaily.com/releases/2008/07/080714094254.htm) Science Daily 1. ^ [***a***](#cite_ref-WoRMS_2023_3-0) [***b***](#cite_ref-WoRMS_2023_3-1) [***c***](#cite_ref-WoRMS_2023_3-2) [***d***](#cite_ref-WoRMS_2023_3-3) Read, G.; Fauchald, K. (Ed.) (2023). World Polychaeta Database. Nereididae Blainville, 1818. Accessed through: World Register of Marine Species at: [https://www.marinespecies.org/aphia.php?p=taxdetails&id=22496](https://www.marinespecies.org/aphia.php?p=taxdetails&id=22496) on 2023-10-27 1. **[^](#cite_ref-4)** [Animal Fact files: Ragworm (*Nereis diversicolor*)](https://web.archive.org/web/20080528060948/http://www.bbc.co.uk/nature/blueplanet/factfiles/segmented_worms/ragworm_bg.shtml) [BBC](/source/BBC) Science & Nature 1. **[^](#cite_ref-MarLIN_5-0)** Budd, Georgina (2008). ["Ragworm: *Hediste diversicolor*"](http://www.marlin.ac.uk/species/detail/1426). *[Marine Life Information Network](/source/Marine_Life_Information_Network)*. Retrieved 2013-05-18. 1. **[^](#cite_ref-6)** Merrit, Mike (13 January 2013) [Sea-change as farm grows fish on land](http://www.scotsman.com/scotland-on-sunday/business/sea-change-as-farm-grows-fish-on-land-1-2734685) The Scotsman, Retrieved 22 January 2013 1. **[^](#cite_ref-7)** Nguyen Quang Chuong (2009). [Some contribution to study on productive characteristics of the palolo (Tylorrhynchus heterochaetus) Polychaeta - Nereidae in Hai Phong brackish water](http://vjs.ac.vn/index.php/vjbio/article/view/4942). 1. **[^](#cite_ref-8)** Pakorn, Jiraporn (2015-09-30). ["ตัวร้อยขาปนมากับน้ำได้อย่างไร อันตรายหรือไม่"](https://www.scimath.org/article-science/item/4777-2015-09-30-04-14-45). *SciMath* (in Thai). Retrieved 2026-04-23. - Santos et al., 2006 [\[1\]](http://www.publish.csiro.au/nid/120/paper/IS05001.htm) - A Key to Families of Polychaetes [\[2\]](http://www.nhm.ac.uk/research-curation/research/projects/taxinfo//key/family_key.htm) - The City University of Hong Kong page on Nereidae [\[3\]](http://personal.cityu.edu.hk/~bhworm/errant/nereidae.htm) - More Information on Nereididae [\[4\]](https://web.archive.org/web/20060501040625/http://folk.ntnu.no/vmzotbak/polychaeta/nereididae/index.htm) Taxon identifiers Nereididae Wikidata: Q1280602 Wikispecies: Nereididae ADW: Nereididae AFD: Nereididae BOLD: 30439 CoL: 84KJY EoL: 108 EPPO: 1NEREF GBIF: 6972 iNaturalist: 49581 IRMNG: 104778 ITIS: 65870 NBN: NHMSYS0021048964 NCBI: 39820 NZOR: 5d6d0d60-0cf0-4e9b-b40f-ca884e2d36b9 Open Tree of Life: 741326 Paleobiology Database: 354974 Plazi: F6469146-AC30-EE5D-67F1-CBCB3923FACD WoRMS: 22496 --- Adapted from the Wikipedia article [Nereididae](https://en.wikipedia.org/wiki/Nereididae) by Wikipedia contributors ([contributor history](https://en.wikipedia.org/wiki/Nereididae?action=history)). Available under [Creative Commons Attribution-ShareAlike 4.0 International](https://creativecommons.org/licenses/by-sa/4.0/). Changes may have been made.